DRY up Geocodio::Client

Extract similar fragments of code responsible for parsing response
bodies into a Geocodio::Utils class.

Signed-off-by: David Celis <me@davidcel.is>
Create new VCR cassettes for reverse geocoding changes

Signed-off-by: David Celis <me@davidcel.is>
Bump version to 1.1.0

Signed-off-by: David Celis <me@davidcel.is>